Furnace for annealing or heat treating.



W. N. BEST.

FURHACE FOR ANNEALING 0R HEAT TREATING.

APPLICATION man Juul-:14. ma.

L, Patented oet. 15, 1918.,

W TT y TT @mgm E l@ a Y, mila/mm3 WILLIAM N. BEST, OF BROOKLYN, NEW YORK.

FURNACE vFOB, ANNEALING OR HEAT TREATING.

Specification of Letters Patent.

rammed oct. 15, 191s.

Application led June 14, 1918. Serial No. 239,962.

To `all ywhom.. it may concern Be it known that I, IVILLIAM N. BEST, a citizen of the United States, and a resident of Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements lin Furnaces for Annealing or Heat Treating, of which the following is a specification.

This invention is a furnace for annealing, hardening, tempering, or other heat treating of metallic or other articles or of crucibles or containers therefor. The main object of my invention is to secure a uniform heat distribution in the chamber adapted for the heat treatment of the articles and particularly7 comparatively `large articles, such as shafts, axles, etc., which are most conveniently moved into and out of the chamber on a car, truck, or other movable platform and supported thereon during said heat. treatment.

As one important feature of my construction for securing the uniform heat distribut-ion, I utilize the plat-form or body of the car or other movable work support and Carrier, as a part of the conduit or passage for the hot gases so that they are brought into more intimate contact with the work, part-s, or articles to be heat treated. the platform with a longitudinal passage having gas ports along its length and open at one end so as to register with the flue in the furnace wall when the platform with its load is in position, the articles along the platform are equally subjected to the heating action.

As another important feature of my improved construction, I provide two separate parallel flame or hot gas passages along opposite sides of the heating chamber and deliver the flame or hot gases in opposite directions lengthwise of these passages 'and admit it along the length of said sides so that all portions of the chamber along its length receive equal quantities of heat.

As another important feature, I establish communication between the heating chamber and the parallel flame or hot gas passage by a series of ports leading from the latter at an angle to the main direction of flame travel, the ports varying in size with the largest nearest to the burner where the velocity past the port is greatest. Thus the. amount of flame or hot gases entering the chamber at all points may be substantially By forming equal irrespective of the distance of said l ports from the burner.

As a further important feature I provide a single arch roof over the heating chamber and flame passage or passages with its axis parallel to the latter and with the high part over the chamber and the downwardly inclined sides of the arch over the flame pas- Sages so that said inclined sides act to defleet the flame and gases and also radiate the heat laterally of the passages on to the articles to be heated.

In the accompanying drawings I have illustrated one embodiment of my invention designed for the accomplishing of the above mentioned objectv and including all of the features above referred to. It will of course be evident that various changes may be made in the details of construction and the arrangement of parts and that constructions embodying certain but not all of the important features thereof may be constructed within the scope of my invention as defined in the appended claims.

In these drawings to which reference is to be had:

Figure 1 is a horizontal section on line l-l of Fig. 3.

Fig. 2 is a central longitudinal vertical section on line 2-2 of Fig. 1.

Fig. 3 is a transverse vertical section on the line 3 8 of Fig. 2 ona larger' scale, and

Fig.. 4 is a sectional detail on line 4-4 of Fig. 1.

In the specific form illustrated the furnace has three main chambers including a heating chamber 10, and two oppositely disposed flame or hot gas chambers or passages 11, 11 separated therefrom by parallel partitions 12. 12.1 The outside wall of the furnace may be of fire-brick or any other suitable material and includes side walls 13, 13 parallel to said partitions and supporting an arch roof 14 covering the three chambers with the high part of the roof over the central or lfeating chamber 10. At one end there is provided an end wall 15 and at the opposite end are walls 16, 16 at the ends of the flame passages 11, 11 and a door 17 for closing the heating chamber.

At one end of one flame passage and at the opposite end of the other flame passage are burner pits 18 receiving burners 19 which latter deliver through diverging passages QO through the walls 16, 16 lengthwise after this has been reached.

of the flame passages 11, 11. Although I may lemploy various different forms of burners in connection with my improved furnace, I preferably employ a ty-pe in which the liquid fuel, such as oil or tar, is delivered through an upwardly facing port across lwhich a blast of compressed air, steam or other atomizing fluid is forced so as to deliver the atomized fuel in a substantially fan-shaped sheet. I have shown somewhat conventionallyv a burner 21 which may be constructed as shown in my vprior Iatents708,453 issued September' 2, 1910 or 752,195 issued February 16,` 1904. Below this may be placed a nozzle 22 for delivering low pressure volume air to support the combustion of the vaporized fuel. Although the burners above referred to are relied upon to raise the heating chamber and the articles tilierein to the desired high temperature, it maybe found desirable and economical to use smaller burners for holding the temperature at the desired point I have shown small auxiliary burners 23 delivering through passagesy 24 adjacent to the burners 19 and their p assages 20. The use of such auxiliary means may be substantially the same as disclosed and claimed in my prior Patent 1,166,807 issued January 4,1916.

The arch roof 14 has its downwardly inclined side portions directly over these flame passages 11, 11 and tends to deflect or divertI the flame and gases laterally and also to radiate laterally the absorbed heat. For aiding in securing the uniform distribution of the heatalong` the length of the heating chamber,'the partitionsy 12, 12 each have a series of ports 25 therethrough, the ports varying in size from one end of the partition to the other. The largest port is disposed adjacent to the burner and of each flame passageI where the flame is traveling at the highest velocity. As the. rate of travel of the flame decreases toward the far end theA ports are smaller in size. The smaller ports opposite the slow velocity gases take substantially the same amount as the larger .ports opposite the high velocity gases, due to the fact that the gases arey traveling in a'V direction at right angles to the directionvof the ports. Each port eX- tends from the upper edge of the partition closely adjacent to the arch roof down to a point determined upon by the level of the support for the articles or parts to be heated.

For supporting the articles tobe heated, .employ a platform 26 of a Width but slightly less than the distance between the two partitions 12, 12 and provide means whereby this'fplatform inay be moved bodily into or out of the furnace. 'has a metal frame-Work 27 supported by a As shown, it

series of wheels 28 movable along a track 2S). The body of the platform above the fralneis formed of fire-brick or other fireresisting insulating material and the sides of the platform or truck have means for cooperating with the partitions to form a seal separating the heating chamber above the platform and the space beneath the platform within which is the supporting wheels and track. One means of forming such a seal includes the use ofehannels or troughs 30 on one each side of the platform into which extend depending flanges 31 on the partitions 12, 12. The troughs are filled with sand so that the truck may be freely moved endwise but the passage of gas beneath the flanges 31 is prevented by the sand. At the end of the truck opposite to the door the end wall 14 may have a trough 32 into which sand may be piled to such a level that the under surface of thc platform will move into or on to the sand and thus form an effective seal.

The end wall 14 of the furnace `has a -flue 33 for the escape of the gases of combustion and this at its lower end turns laterally and registers with a flue or passage 34 in the body of the platform 26 and extending lengthwise of the latter. A series of ports 35 lead from this flue 34 to the upper surface of the platform so that the gases which are delivered laterally into the heating chamber through the ports 25 may pass over and around the articles to be heated and ldown through the ports 35 to the flue 34. By supporting the articles to be heated such for instance as large shafts or axles on restblocks 36, thegases may pass beneath as well as over the said shafts or axles from the ports 25 to t-he ports 35 and effectively and -uniformly heat them from one end to the other. To aid inpreventing the space beneath the platform from being too highly heated, the door 17 is preferably mounted to move vertically and when in lowered position rest directly upon the end of the platform so that the outside air may .freely circulate beneath the platform and around the wheels and bearings of the truck.

The various walls of the furnace may be reinforced, supported or held in place in any suitable manner and suitable pyrometer openings 37 may be provided in the arch roof as well as peepholes 38 in the end walls adj acent to the burners, whereby the operation may be observed and controlled. So far4 as the actual heating operation and the unipreferably employed `where the parts to be heated are heavy or moved with difficulty when in heated condition.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A furnace, having a heating chamber, separate flame passages extending lengthwise thereof along opposite sides and communicating therewith through said sides, means for delivering flame lengthwise of one of said passages from one end thereof, and means for delivering flame lengthwise of the other passage from the opposite end thereof.

2. A furnace, having an arch roof, substantially vertical partitions extending lengthwise thereof therebeneath, and forming a heating chamber beneath the. high portion of the arch, and flame passages beneath the downwardly inclined side portionsof the arch, and means for delivering flame lengthwise of said passages, saidpartlitions having portions of their upper edges spaced from said roof to permit the .upward flow of gas along lsaid roof from said passages to said heating chamber.

3. A furnace, havingan arch roof, recticulated substantially vertical partitions extending lengthwise thereof therebeneath, and forming a heating chamber beneath the high .portion of the arch, and flame passages beneaththe downwardly inclinedside portions of the arch, and means for delivering flame.

lengthwise 4of said passages in one direction 1n one Vpassage and 1n the opposite direction in the other passage.

4. A furnace, having a heating chamber,

separate flame passages extending lengthwise thereof upon opposite sides and 'separated therefrom by partitions, said partitions having portstherethrough along the length thereof and larger at one end than at -the other, and means for delivering flame lengthwise of each passage from the end thereof adjacent to the largest ports in said partitions.

5. A furnace, having a heating chamber, a

-flame passage extending yalong one side thereof from one end tothe otherand separated therefrom by a substantially vertical i partition, and means` for delivering llame to one end of said passage lengthwise there-` of, the top wall of said' passage being inclined downwardly away'from said heating chamber, and said partition having passages therethrough closely adjacent to said top wall whereby the flame and hot gases are deflected laterally toward said heating chamber.

6. A furnace, having a heating chamber, a flame passage extending lengthwise thereof along one side, a partition separatin'gsaid chamber land said passage and having a series of ports therethrough of varying sizes,

eating with the latter through spaced ports along the length of said floor.

`8. A furnace, having a heating charnblar,l

the work supporting floor or platformthereof having a passage extending lengthwise Y thereof and communicating Vtherewith through a series of spaced vents, side walls for said heating chamber having a series of ports therethrough, and means for delivering flame and hot gases along the outer sur- 'f faces of said side walls in one direction on.y y l one side and in the-opposite direction on the other side. 4

9. A furnace, having a heating'chamber, provided with spaced inlets along opposite sides thereof for delivering the flame or. hot gases transversely thereof and a longitudinal movableplatform. or work support provided with a passage extending lengthwise thereof, and spaced vports leading from said passage4 to the upper surface thereof along the length of said platform, and an escape flue adapted to register with s aid passage when said platformY is in position.

10. A furnace,including a work support platform, an arch roof extending over 4the same, means for delivering llame lengthwise beneath the side portions of said a'rch in o posite directions upon opposite sides of said platform, and a ventflue extending lengthwise through'sa'id platform. e

Signed at Brooklyn in the county of Kings A. D. 1918. v A.

WILLIAM N. BEST.

and State of New York this 7th dayof June 

